Hi, all. I'm an E91 owner and a longtime contributor to the audio sections in the E90 and 1Addicts sections, well before we became a sponsoring Authorized Vendor. This post has nothing to do with selling you anything - we got our first crack at an F30 and we are doing some development work in it, and we thought we'd share some of the results of our testing.

The car we worked on today is an F30 328i Sportline with Premium Sound ("harman/kardon"). In addition, we had a HiFi door mid on order for a long time, and it finally arrived, so we can contrast the differences between hk and HiFi mids a bit.

The system has front mids and tweeters in the doors, a center channel, rear door and rear deck speakers, and woofers under the seat.

Today we looked at:

- The door mids
- The door tweeters
- The signal going to the door speakers
- The underseat woofers
- The signal going to the underseat woofers

Tomorrow we will look at more test results.

Door mids, tweeters, and signal

Well, BMW has changed the door midrange a good bit. Instead of bolting the speaker to the back of the door panel, the speaker actually bolts to the sheet metal - using the entire door as the speaker chamber - and then the front of the speaker mates to the back of the door panel with a gasket.

Since the speaker is bolted into a hole in the sheet metal, it is exposed to water. The hk speaker is made of pretty water-resistant materials (injection-molded frame, synthetic rubber surround, poly cone), and has what looks like a 30mm voice coil (larger than most 4" speakers) The HiFi speaker is made of paper and foam and has a more common 25mm (1-inch) voice coil.

The magnet is right up against the window glass. You might be able to go in another mm, but no more than that.

The speakers which people (including us) have often been using in E90 front doors will NOT fit the F30. The speakers we have been using in the E92 can fit and seal up with some spacer development which we are now working on. Whatever adapter is used needs to both mount the speaker to the BMW mounting holes and act as a spacing gasket against the back of the door panel.

I didn't take pics of the tweeter. The tweeter size is unchanged from the E9x and other BMWs. The odd thing about the hk tweeter is the series capacitor - it's gotten hugely upgraded. It's a 4.7uf mylar job, that quite literally is huge - the largest capacitor I've ever seen on a tweeter in an OEM system, and the first mylar I've noticed. Funny how harman, with all their faith in DSP, has decided to use a more costly part in a crossover filter that actually adds to the bill-of-materials cost. They must really believe it helps.

The electrical signal to the front doors looks like this:

(Please note that this is NOT the acoustic response measured with a microphone - this is the electrical response measured on the speaker wires, with the system playing pink noise and the tone controls and EQ all flat).

There is much more equalization going on than the E9x Premium Sound systems used. The crossover looks to be a bit lower, which I would expect, with the 4" speaker being in the door chamber like this - the upper bass should be better than the E9x cars. With any aftermarket speaker, I would expect the dramatic roller-coaster curve would need to be corrected.

Underseat woofer and signal

The underseat woofers in the F30 are listed in at least instance by BMW as "217mm" speakers where the previous Bangle cars all were using "200mm" speakers. They are the same diameter. However, the magnet on the hk woofer is larger than before, and it uses a 3-inch voice coil (like the E9x Enhanced Premium woofers). Like the EP woofers, the impedance of the underseat woofers is around 7 ohms. The signal to the woofer hits 28V on my meter, which is not a true RMS meter, so it's not as high a peak as the EP system's 36V. Tomorrow I will measure the DC content - I have a strong suspicion that the amp is a Class D and that regular signal-sense devices won't work on the outputs.

The woofer on the left is a Logic 7 woofer, the right is the F30 hk woofer (I don't have an E9x hk woofer from the 2010 audio reintroduction of hk handy).

What I didn't get a good picture of is the decrease in depth. The F30 has a much shallower enclosure than other BMWs we've worked on, and the speaker/spacer combos which have been used in the E9x and the E82, etc., again won't fit, I'm afraid. We are working on some solutions.

The signal to the underseat woofers is also heavily EQd, but it seems to be fixed in EQ curve:

The peak is at 50 cycles, and the curve is 14dB down at 20 cycles, so there is a meaningful subsonic high-pass filter in use. This could limit the performance of a trunk sub connected to this low-passed signal (it probably will, without some kind of correction).

Other notes:

- The door panels are surprisingly lightweight. Unlike the E9x door panels, I highly recommend damping them with something, and we will be including something in our F30 kits.

- The hk amplifier has the external power connector like the EP amps. This is another indication that the amp is a "real" amp, not a BTL amp like the Logic 7 and hk amps were for the E9x and E82.

- For bigger systems, the well in the trunk floor is much easier to get wiring into than the well in a 325/328/330 E9x trunk.

- as we expected, the PnP Premium Sound harness fits the hk amp in the F30.

What we have learned so far

- I don't think anyone is dropping SWS in there anytime soon. I suspect they will hit the bottom of the grille if spaced up enough.

- There are some front and underseat speaker upgrades we will be able to offer very soon after some parts development.

- Many amps will clip on that 28V peak signal to the underseats

- With the heavy-handed EQ, I suspect that simple speaker upgrades won't be effective and corrective processing will be even more important than ever. I would want the DA2 in an HK car for a full system, and I might even want some DSP for a subwoofer add.

Tomorrow - acoustic measurements with a microphone, a cursory look at the center and rears, a closer look at the amp, listening tests, and more.

...Whatever adapter is used needs to both mount the speaker to the BMW mounting holes and act as a spacing gasket against the back of the door panel....

I'm really happy that this thread started and thanks for that. I thought I'm sharing some of the picture I took of my partly done install (6ch BASE system with no amp -> upgrade with MS-8 + amp(s)). Will start my own thread sometime later as the upgrade didn't really meet with my expectation yet in terms of SQ improvement and wanna ask some advice.

As someone who got his career started with a 12V job at a high end local company, I can honestly say I have zero desire to mess with the audio in this car. This is my third H/K equipped car and I think it sounds the best (previous was a '10 MB E550 Coupe and current SRT8). I've done elaborate installs on other cars and am happy these days that I can get a respectable setup for not much $$$ in a factory system (which frankly has been the death of the small independent shop).

That's not to say I won't be following this thread....I will because I dig it.

This will be tough - as I understand it BMWNA has dropped the base Stereo system again from this market. The Stereo unamplified level of BMW sound system hasn't been seen in the 3-Series in the US since the E30. E36, E46, and E9x until 2010 all had HiFi - the middle system - as standard, and Premium sound as an option. 2010 and early 2011 were an aberration - we had Stereo as standard and no HiFi (other than in the M3). My guess is that we in the States are unlikely to see Stereo here, just HiFi and Premium Sound (branded h/k). If someone in the rest of the world wants to do this sort of measurement with a PC, I can walk you through about $100 in parts needed to do so (or if someone wants to fly me to Sydney or Europe ) because I would love to do it. AFAIK we were the first to do this sort of analysis in the US on 2010 base Stereo signals in the E82 and E9x. I expect it to be front mids, rear mids, underseat 6", and deck power with a preset EQ curve looking like a jagged happy face, which is what it looks like in the E82, E70, and E9x (the curve is different but in each case severe enough to compromise upgrades which don't correct it).

Quote:

Front speaker adapter made from MDF:

That MDF ring you made had better have a lot of coats of paint on it, because it's getting wet from the backside and when MDF gets wet, it expands.

This was what I found in my niece's preowned VW Beetle when I was installing new speakers for her. It's about 1" thick in this picture, but it was originally 3/4" MDF:

As far as your expectations, it's known that the E90 and E82 base Stereo systems use extensive EQ on the speaker leads, and I see no reason to think the F30 is different. I would expect better speakers than you used to sound poor in that scenario without correction, I'm afraid.

Quote:

This is my third H/K equipped car and I think it sounds the best...

I agree that it sounds better than other HK systems (in BMWs, I have not listened critically to many other HK branded systems, but they are always limited by the OEM's willingness to spend on HW), but I thought all the other HK systems in BMWs sounded like ass anyway. This is the first F30 we've been able to investigate, and we are working on a trunk-sub-add option for it.

I'd love a trunk mount sub for my 300C. The stock 10" is in the rear deck and combined with the 6x9's back there, there's quite a bit of noise. I tore it down this past weekend and taped down wiring and such, along with putting a few layers of sound mat on the more noisy sections of sheet metal (there was almost nothing from the factory ). It helped, but not much.

There's an alternative "Beats Audio" system that uses dual trunk mounted subs that solves that problem. How that system is amplified vs. the HK system would be interesting to know (i.e. is there an off-the-shelf solution or one that can be created with minimal effort).

So here are some acoustic measurements. Please remember that sound at a given note is not neccesarily good sound. Impulse response and distortion play a huge role. The F30 HK system did sound tons better than the E90 HK system, but it was still bright and forward to me (see below).

With the EQ and the tone controls flat, Logic 7 off

With the bass control up 50%:

With the 10k EQ slider up 50% (not recommended for listening):

The settings I liked best myself were the bass control up three clicks and 100 Hz down 50%, 2k down three clicks, 5k down two clicks, and 10k up 2 clicks. This seemed to be the least annoying. The Logic 7 surround feature turned on would make the system sound much brighter and I didn't like that, but I did find the hk system bright in my listening (my 2k cut was to try to get rid of the brightness, but it wasn't completely successful).I'm pretty certain that my settings are not as flat as that pretty flat initial curve, but it sounds better to me.

Since I have limited knowledge in regards to all the sound technicalities, and since you ARE an expert at it, I have a simple question.
Is it worth upgrading to an $875 HK system? All I care about is it should have good bass and should sound 'clean' even at high volume.

My response is that it's one of the best OEM systems I've heard, but I would listen to it with my own music before ordering.

I find bright, forward systems fatiguing to listen to for long. The bass is a bit boomy. it's not as good as what we do, but it's one of the best stock systems out there. We will be offering a PnP trunk-sub option for this hk system as well as full cabin upgrades for the HiFi systems.

Quote:

So, you would say overall, the F30 HK system is a step up from the 2011 E90 HK system?

No. Two steps. It's very comparable to the Enhanced Premium system in the E9x M3 and M5. Bass is flabbier, less controlled, but louder.

I doubt we will get anyone wanting to upgrade HK systems other than demanding audiophiles. We will get many more wanting to add sub-bass, and of course we will get HiFi upgrade requests. If only I could get my hands on a 6-speaker car...

If someone in the rest of the world wants to do this sort of measurement with a PC, I can walk you through about $100 in parts needed to do so (or if someone wants to fly me to Sydney or Europe ) because I would love to do it.

It's not sunny Sydney but rather rainy Brussels , but I'm willing to help if time permits. I know very little about car audio and after reading a bunch of topics for the E90, I already installed MS-8 with upgraded front speakers, but if you think at this stage I could still do some measurements, please let me know. I believe I'd be able to benefit from this too.

I'm at this stage right now:
- Front OEM's replaced by Polk dxi400
- Center speaker installed. This is tricky, as you need to cut dashboard. Speaker is same as above.
- Still OEM rears and OEM woofers
- MS-8 driving all above

I have some tools, like DMM, laptop with REW installed (never used though) which could probably take measurements with the MS-8 mic (?)... I'm going to remove the front door panel soon in order to double check some wiring, so if I'd need to reinstall OEM fornt for measurement, in theory that could also be done.

It could also be due to the fact that I've been exposed to really high-end studio systems as a mixing/mastering engineer.

Even my 7-year old system with most of it's speakers dying out, running in a 2.1 with a Polk Sub config sounds better, lol. I found the HK to be tinny and a bit harsh. It could have been the quality of the audio the dealer showed me as I haven't received the car yet.

To make it sound better, he kept boosting the highs, which generally isn't a good idea. The more highs you boost especially 10K, the thinner your mids/bass will get and also causes more ear fatigue. Most car systems are tuned to pump out more bass.

The HK bass response didn't seem tight either. From the graphs shown in this thread, Bass Control seems to boost 80Hz.

While in my remote location, I won't be able to modify or replace the HK, I hope a marginal satisfaction can be reached using the EQ's. Why has BMW made this so complicated? In all honesty, HK sucks, not sure how much of an improvement it is over the stock system.

Can you at least replace the centre dash Tweeter without affecting the response too much? A Focal tweeter can bring in the much needed clarity.

VP Elec, great thread, very informative. In the meantime, once I receive the car, I'm going to try squeezing out the car EQ.

I find bright, forward systems fatiguing to listen to for long. The bass is a bit boomy. it's not as good as what we do, but it's one of the best stock systems out there.

I doubt we will get anyone wanting to upgrade HK systems other than demanding audiophiles. We will get many more wanting to add sub-bass, and of course we will get HiFi upgrade requests. If only I could get my hands on a 6-speaker car...

Thanks for your analysis. I listen to bassheavy electronic music. Trance, goa, house... For me, the bass is way too boomy and not really focussed.

I would like to lower the frequencies below 60hrz without loosing the 80 - 120 hrz spectrum but the equalizer only supports 100 hrz.

Did you analyse the difference between the "Bass knob" and the 100 hrz equalizer? Is it the same?

My response is that it's one of the best OEM systems I've heard, but I would listen to it with my own music before ordering.

I find bright, forward systems fatiguing to listen to for long. The bass is a bit boomy. it's not as good as what we do, but it's one of the best stock systems out there. We will be offering a PnP trunk-sub option for this hk system as well as full cabin upgrades for the HiFi systems.

I'd say my only worries for the HK system were:
1 - Is the amp a real Class D amp and does it provide sufficient quality power to all the speakers? (appears to be, doesn't really distort at higher vols)
2 - Can the woofers handle bass heavy music? (passable, but even a single 12" sounds better)
3 - Are the tweeters too bright? (a little, but I've heard much worse)

I did a similar exercise w/ an RTA, trying to smooth out the EQ curve. And it sounds better after doing that. I turned of Logic7 as well.

VP Electricity - thanks for sharing all this info! Looking forward to see the finished trunk sub results.